• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.4
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• pp.825-840
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• 2015

Adaptive bitrate (ABR) streaming technology has become an important and prevalent feature in many multimedia delivery systems, with content providers such as Netflix and Amazon using ABR streaming to increase bandwidth efficiency and provide the maximum user experience when channel conditions are not ideal. Where such systems could see improvement is in the delivery of live video with a closed loop cognitive control of video encoding. In this paper, we present streaming camera system which provides spatially and temporally adaptive video streams, learning the user's preferences in order to make intelligent scaling decisions. The system employs a hardware based H.264/AVC encoder for video compression. The encoding parameters can be configured by the user or by the cognitive system on behalf of the user when the bandwidth changes. A cognitive video client developed in this study learns the user's preferences(i.e. video size over frame rate) over time and intelligently adapts encoding parameters when the channel conditions change. It has been demonstrated that the cognitive decision system developed has the ability to control video bandwidth by altering the spatial and temporal resolution, as well as the ability to make scaling decisions.

• Journal of KIISE:Software and Applications
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• v.31 no.9
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• pp.1142-1149
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• 2004

Motion Estimation(ME) has been developed to reduce temporal redundancy in digital video signals and increase data compression ratio. ME is an Important part of video encoding systems, since it can significantly affect the output quality of encoded sequences. However, ME requires high computational complexity, it is difficult to apply to real time video transmission. for this reason, motion estimation algorithms with low computational complexity are viable solutions. In this paper, we present an efficient method with low computational complexity based on spatial and temporal correlations of motion vectors. The proposed method uses temporally and spatially correlated motion information, the motion vector of the block with the same coordinate in the reference frame and the motion vectors of neighboring blocks around the current block in the current frame, to decide the search pattern and the location of search starting point adaptively. Experiments show that the image quality improvement of the proposed method over MVFAST (Motion Vector Field Adaptive Search Technique) and PMVFAST (Predictive Motion Vector Field Adaptive Search Technique) is 0.01～0.3(dB) better and the speedup improvement is about 1.12～l.33 times faster which resulted from lower computational complexity.

• Tunnel and Underground Space
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• v.20 no.3
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• pp.153-168
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• 2010

A fifth equation is required to determine the five independent elastic constants of a transversely isotropic rock from compression test of a single specimen. As an approximation proposed by Saint-Venant has been used for long time, it may cause an erroneous result in some cases, especially for specimen with low angle of anisotropy. Three equations were suggested replacing this traditional equation and proved to be applicable by the model analysis in the previous studies. As Saint-Venant's approximation is turned out the same as the first one of them, it has the characteristics that the apparent Young's modulus is monotonously increasing according to the anisotropic angle. The methodology to analyze the elastic constants from four independent strain measurements by uniaxial compressive test of a single standard specimen is concisely described, and the necessity and compatibility of new suggested equations are discussed. Saint-Venant's approximation can determine the elastic constants close to true values and other equations may be unnecessary in specimens with medium to large angle. Nevertheless, they may become applicable because they can produce the almost same amount. For the specimens of small angle of anisotropy, Saint-Venant's approximation may result in out of general ranges or thermodynamic constraints, but other suggested equations can produce the almost true value. Thus they can be applied before other alternative equation is known. The guide map constructed by model study may decide the most compatible one of the three equations.

• Journal of Broadcast Engineering
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• v.14 no.3
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• pp.322-331
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• 2009

This paper proposes an efficient data representation of stereo images using edge-based mesh optimization. Mash-based two dimensional warping for stereo images mainly depends on the performance of a node selection and a disparity estimation of selected nodes. Therefore, the proposed method first of all constructs the feature map which consists of both strong edges and boundary lines of objects for node selection and then generates a grid-based mesh structure using initial nodes. The displacement of each nodal position is iteratively estimated by minimizing the predicted errors between target image and predicted image after two dimensional warping for local area. Generally, iterative two dimensional warping for optimized nodal position required a high time complexity. To overcome this problem, we assume that input stereo images are only horizontal disparity and that optimal nodal position is located on the edge include object boundary lines. Therefore, proposed iterative warping method performs searching process to find optimal nodal position only on edge lines along the horizontal lines. In the experiments, we compare our proposed method with the other mesh-based methods with respect to the quality by using Peak Signal to Noise Ratio (PSNR) according to the number of nodes. Furthermore, computational complexity for an optimal mesh generation is also estimated. Therefore, we have the results that our proposed method provides an efficient stereo image representation not only fast optimal mesh generation but also decreasing of quality deterioration in spite of a small number of nodes through our experiments.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.11
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• pp.290-296
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• 2017

Purpose: The purpose of this study was to compare the effects of CPR training according to the mannequin used for CPR training using Little $Anne^{(R)}$, $BRAYDEN^{(R)}$, and $HeartiSense^{(R)}$. Method: Research subjects were 90 firefighters who were not paramedics. They were divided into three groups, A, B, and C. Theoretical education was conducted for 50 minutes, and practical education was conducted in groups of three for 50 minutes, using Little $Anne^{(R)}$ for 30 people in Group A; $BRAYDEN^{(R)}$ for 30 people in Group B; and $HeartiSense^{(R)}$ for 30 people in Group C. The results of CPR were printed out using Resusci Anne $SkillReporter^{(R)}$, and the subjects were asked to fill in a questionnaire. Results: The following significant differences were noted: satisfaction index according to the mannequin, $x^2=81.050$, p<.000; reason for satisfaction, $x^2=91.050$, p<.000; ratio of accurate chest compression, F=5.087, p<.004; and ratio of accurate ventilation, F=10.54, p<.000. Conclusion: For the subjects who require accurate and efficient CPR training, it is judged that a mannequin that provides information to allow corrections in real-time would be effective, and have a high educational effect.

• Journal of the Korean association of regional geographers
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• v.20 no.4
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• pp.357-378
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• 2014

The concern on new regional geography in Korea has emerged in the 1990s under the influence of paradigm shift of Western geography, that is, the withering of positivist geography and the introduction of grand social theories into geography. New regional geography in Korea also seems to have developed in the rapidly changing process of glocalization of capitalism which has accompanied with the transformation toward post-Fordism with high-tech innovation, development of transportation and communication technology with time-space compression, and increasing social and cultural mobility with change of identity. But it can be pointed out that discussion on methodology for regional geography in Korea has been shrunken since the mid 2000s, and there has been relatively little empirical research with synthetic approach to region. But more concern on methodology in terms of place, territory, network, scale, etc. rather than the concept of region itself has increased, and empirical researches on regions in specific fields of human geography have been promoted. It is argued that the traditional distinction between synthetic and analytic approaches seems no longer significant. But geographers need to extend the concept of region in relation to other diverse spatial concepts, and to purse simultaneously structural analysis on glocalization process and practical strategies responding positively to the process.

• Journal of Korea Multimedia Society
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• v.10 no.11
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• pp.1427-1438
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• 2007

Video watermarking technologies are classified into types of four kinds. The first type is to embed the watermark into a raw video signal and to code the watermarked video signal. Most of video watermarking technologies fall into the category of this type. The second type is to apply watermarking to the coding process, such as block DCT and quantization. The third is to directly embed the watermark into the compressed bitstream itself. Generally, it is referred as labelling rather than watermarking. Finally, the fourth is to embed the water mark into MPEG motion vector. This type has the difficulty in real-time process because of the high complexity and has the blocking effects because of DCT-based on coder. In this paper, we proposed the digital video watermarking that embed the watermark in SPIHT video code for I-frame using motion vector analysis. This method can remove the blocking effect occurred at the DCT-based on coder and obtain video data that has progressive transmission property. The proposed method is to select the region for the watermark embedding in I frame using motion vector estimated from the previous P or B frame. And then, it is to perform DWT and embed the watermark based on HVS into the wavelet coefficients in the same subband of DWT as the motion vector direction. Finally, the watermarked video bitstream is obtained by the SPIHT coder. The experimental results verified that the proposed method has the invisibility from the objective and subjective image quality and the robustness against the various SPIHT compression and MPEG re-code.

• Journal of Korea Multimedia Society
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• v.15 no.6
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• pp.805-813
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• 2012

In this paper, we have designed and developed a middleware for an effectively approaching database to the existed brain disease clinical research system. The brain disease clinical research system was consisted of two parts i.e., a register and an analyzer. Since the register collects the registration data the analyzer yields a statistical data which based on the diverse variables. The middleware has designed to database management and a large data query processing of clients. By separating the function of each feature as a module, the module which was weakened connectivity between functionalities has been implemented the re-use module. And image data module used a new compression method from image to text for an effective management and storage in database. We tested the middleware system using 700 actual clinical medical data. As a result, the total data transmission time was improved maximum 115 times faster than the existing one. Through the improved module structures, it is possible to provide a robust and reliable system operation and enhanced security functionality. In the future, these middleware importances should be increased to the large medical database constructions.

• The Journal of Korean Obstetrics and Gynecology
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• v.33 no.2
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• pp.77-89
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• 2020

Objectives: The purpose of this study is to analyse current status and treatment of the Korean medicine hospital after chemotherapy in patients with breast cancer. Methods: We investigated the medical records of 21 patients who admitted to Korean medicine hospital after chemotherapy in patients with breast cacner from March 1, 2017 to December 31, 2019. We searched medical records retrospectively and analyzed current status and treatment of Korean medicine hospital. Results: The average age of 21 participants was 52.81±8.38 years and 40s and 50s accounted for 85.6% of the total. After receiving chemotherapy, the average time to hospitalization was 1.87±3.13days and average hospital stay was 9.78±4.14 days. The subjects were classified as 28.6% of stage I, 52.4% of stage II, 9.5% of stage III, and 9.5% of stage IV. The analysis according to the presence of metastasis was 57.1% without metastasis, 33.3% with axillary lymph node metastasis, and 9.5% with distant metastasis. The main symptoms complained when hospitalized by 21 subjects were nausea (54.2%), fatigue (54.2%), and anorexia (50.8%) in over 50%, pantalgia (47.5%), and insomnia (47.5%), dizziness (44.1%), cold sweating (42.4%), lower extremity pain (40.7%), 37.5~37.9℃ fever (39.0%), headache (37.3%), hot flush (37.3%), pruritus (30.5%) are 30% or more. Korean medicine treatment was performed in 87.4% of all hospitalizations and Gwakhyangjunggi-san-gami was the most administered prescription. Extracts of Korean medicine was performed in 100.0% of all patients and Eunkyo-san was most administered extracts medicine. Acupuncture, moxibustion, and cupping treatments were performed in all 21 study subjects. Other treatments was performed at a frequency of hyperthermia (90.5%), lymph massage (23.8%), air compression therapy (23.8%), and Interference current therapy (19.0%) Conclusion: Korean traditional medicine can be used as a countermeasure for side effects after chemotherapy in breast cancer patients.

• Journal of the Korean Wood Science and Technology
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• v.3 no.1
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• pp.3-15
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• 1975

How to stabilize wood against shrinking and swelling in variable atmospheric moisture conditions is important to the wood-using industry and a challenge to research. Polyethylene glycol stabilize wood by bulking the fiber. PEG also serve as a chemical seasoning agent, suppress decay in high concentrations, and have slight effect on physical properties, gluing or finishing. The study designed to determine the effect of PEG-400 on the dimensional stabilization of local hardwoods for wood carvings that could supply a greatly expanding tourist trade and making curved furniture parts, lamp stands and other decorative objects, and possible gunstock. The species examined were 6 species, Seo-Namoo (Carpinus laxiflora), Cheungcheung-Namoo (Cornus controversa), Gorosae-Namoo (Acer mono), Karae-Namoo (Juglans mandshurica), Jolcham-Namoo (Quercusserrata) and Sanbud-Namoo (Prunus sargentii), used as block of 5cm thick radially to the grain, 7cm wide tangentially, and 70cm long parallel to the wood grain. All these test piecies were conditioned above the fiber saturation point before impregnation. The stabilization effects were determined for PEG-400 treated woods in a 50 percent solution for 20 days. The following conclusions were obtained. PEG retentions increased with treating time. It was more effective to treat at 60$^{\circ}C$ than at room temperature. In degree of PEG-400 impregnation on species, Cheungcheung-Namoo havinglow specific gravity had the highest retentions, 68.77% but the lowest, 56.33% was shown in Jolcham-Namoo with high specific gravity. Specific gravity of treated wood increased considerably with effectiveness of polymer loading. The increases in specific gravity were 5.36 to 13.16 percent. The highest was Jolcham-Namoo, the lowest Karae-Namoo. On the dimensional stability, a 40 percent of effectiveness of polymer loading was just as effective as 60 percent in reduction in water absorptivity (RWA), antishrinkage efficiency (ASE) and antiswelling efficiency (AE), and from over 60 percent they increased more rapidly. Also species response varied considerably. ASE was 30.12 to 69.97 percent tangentially and 27.86 to 56.37 percent radially, AE 34.06 to 73.76 percent tangentially and 30.11 to 70.12 percent radially, and RWA 42.31 to 65.32 percent. No differences in volume swelling among the 6 species were observed. Its values were ranged from 14.98 to 19.55 percent and also increased with PEG retentions. On the mechanical properties, the strengths very much decreased with PEG-400 loadings as shown in Figure 12; that were 11.41 to 22.90 percent in compression, 21.61 to 34.35 percent in bending and 22.83 to 36.83 percent in tensile strength. PEG retention in cell wall was less than 1 percent and the most of PEG were immersed in cell lumen. Except for Korae-Namoo, effectivenesses of polymer loading were as much high as 61.58 to 75.02 percent. This is believed to be due to the effect of PEG-400 on excellant dimensional stability of treated woods.